﻿#define PI
#define DEBUG
#define VC_V10
using System;

namespace demo10
{
    class Program
    {
        static void Main(string[] args)
        {
            // #define  预处理器
            #if (PI)
            Console.WriteLine("PI is defined");
            #else
            Console.WriteLine("PI is not defined");
            #endif
            Console.ReadKey();

            // 条件指令
            #if (DEBUG && !VC_V10)
            Console.WriteLine("DEBUG is defined");
            #elif (!DEBUG && VC_V10)
            Console.WriteLine("VC_V10 is defined");
            #elif (DEBUG && VC_V10)
            Console.WriteLine("DEBUG and VC_V10 are defined");
            #else
            Console.WriteLine("DEBUG and VC_V10 are not defined");
            #endif
            Console.ReadKey();
        }
    }
}
